Changing the location of panels in different categories in the Toolshelf (script needed)
This Addon could be of your interest. Using it You could create your own panels and then move the existing ones to them. This way its possible to have for example all the architecture addons (Archimesh, Archipack...) in one panel called Architecture.
https://blenderartists.org/t/addon-ui-tabs-change-category/649585